package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {
    // 开始时间戳 2024-09-12-0-0-0
    private static final long BEGIN_TIMESTAMP = 1726099200L;
    // 序列号位数
    private static final int COUNT_BITS = 32;

    private StringRedisTemplate stringRedisTemplate;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    public Long nextId(String keyPrefix){
        // 1. 时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond-BEGIN_TIMESTAMP;

        // 2. 序列号
        //2.1 获取当前日期，精确到天
        String date =  now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        // 3. 拼接返回
        return timestamp << COUNT_BITS | count;
    }

    /**
     * 获取当前时间戳
     * @param args
     */
    public static void main(String[] args) {
        LocalDateTime time = LocalDateTime.of(2024,9,12,0,0,0);
        Long second = time.toEpochSecond(ZoneOffset.UTC); // 1726099200
        System.out.println("second=" + second);
    }
}
